Seeking a way to ease a shortage of donor organs

Numerous patients with incurable diseases are waiting for organ donations, but to no avail. That is because there is a strong demand for available organs, but few donors.
There is the hope, however, that one day the organs of pigs or chimpanzees can be transplanted in humans to treat diseases.
That time may come in the foreseeable future due to the work of people such as Curie Ahn, 50, a doctor of internal medicine at Seoul National University’s medical school.
Dr. Ahn is leading a group of 30 researchers, including heart, lung and pancreas surgeons and breeders of genetically modified pigs, who aim to make interspecies organ transfers possible.
In a laboratory at Seoul National University Hospital in Yeongeon-dong, Seoul, the researchers are experimenting on transplanting pigs’ organs in other pigs and other animals.
A team of surgeons at the hospital led by Lee Jeong-ryeol performed heart transplant surgery on pigs last month, and similar experiments are scheduled for this month.
“It is going to be medically viable to transplant pigs’ hearts or kidneys into humans in 10 to 20 years,” Dr. Lee said. “Then patients with incurable diseases won’t need to wait so long for organ donations.”
Dr. Lee has specialized in kidney transplants and research on the rejection of organ transplants. He has studied the types of immune system reactions that occur after organ transplants and the necessary medical treatments to counteract them. Now, his research is focusing on how to minimize human immune system resistance resulting from pig-to-human organ transplants.
The biggest obstacles are the rejection of a transplant and viral infections. If these problems are solved, transplanting pigs’ organs into humans could be feasible in the near future, Dr. Ahn said.
In the past, Dr. Ahn devoted herself to medical treatment rather than research because she thought that being in a research laboratory was a luxury when there was not even enough time to deal with her patients. She has led a group of volunteers in providing free medical services for migrant workers for the last seven years.
Dr. Ahn initiated the research in 2000, however, after she was introduced to Hwang Woo-suk, a professor of veterinary medicine at Seoul National University, who was the first scientist in the world to succeed in growing stem cells from cloned human embryos.
They did not really know each other at that time because of their different specializations.
Mr. Hwang succeeded in producing genetically modified aseptic miniature pigs, whose organs are considered most suitable for transplants in humans, since the size of the pigs’ organs is similar to that of humans.
The pigs have a relatively short gestation period and give birth to as many as 10 at a time. It is also easier to manipulate the genes of pigs than other animals.
The pigs are produced for this purpose only in the United States and Korea.
Among the various possible applications for such research, Dr. Ahn is initially working on the treatment of diabetes. She plans to mass produce pancreatic cells from genetically modified aseptic pigs for transplant into humans.
The number of patients in Korea with diabetes, which is incurable, has risen 2.5 percent every year, and many patients develop serious complications.
The group of researchers including Dr. Ahn has succeeded in extracting pigs’ pancreatic cells manually, but she said the ultimate goal is to automate the extraction process to regularly produce a certain number of the cells for transplants.
The research team will experiment with transplanting pigs’ pancreatic cells into chimpanzees this year. If successful, the interspecies transplants can be applied to humans in a few years.
“There are too many obstacles to transplanting pigs’ organs into humans [now],” Dr. Ahn said, “but they can be overcome.”
She said she hopes to have access to a lab where all the team members can work together on research. Biochemistry is a field in which researchers, doctors and veterinarians with different specializations should work together on research, Dr. Ahn said, but because they currently are scattered in their own labs, it is difficult to improve efficiency.

by Park Bang-ju, Limb Jae-un